Semiconductors have scores of electrical interconnections required to make electrical contact between the various circuit components. A common electrical interconnect is known as a bond pad. A bond pad is an interconnect from the electrical integrated circuit to a point external to the integrated circuit. Typical bond pads are formed of an aluminum alloy containing a small percentage of copper. The semiconductor process which is used to form an opening in the semiconductor device to form the bond pad typically leaves residual chemicals on the surface of the bond pad location. One of the residual chemicals is fluorine (F). Subsequent formation of the bond pad results in the copper and aluminum used in the bond pad reacting in a fluorine environment. This reaction typically results in localized corrosion of the bond pad. For example, the bond pad may develop pits or holes and negatively affect the subsequent processing of the semiconductor device. For example, the increase in surface roughness of the bond pad results in less reliable adhesion of subsequent ball bond contact to the bond pad. The non-stick phenomena on the bond pad results in yield loss from the wire bonding process.
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